Question

Question #3: In a manufacturing process, a random sample of 9 manufactured bolts has a mean...

Question #3:

In a manufacturing process, a random sample of 9 manufactured bolts has a mean length of 3 inches with a variance of .09 and is normally distributed.

  1. What is the 90% confidence interval for the true mean length of the manufactured bolt?   Interpret your result.   

b. How many manufactured bolts should be sampled in order to make us 90% confident that the sample mean bolt length is within .02 inches of the true mean bolt length?      

Math   Statistics-And-Probability   
0 0
Add a commentTranscribed image text
Next >

Homework Answers

Answer #1

0 0
Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Log In

Sign Up

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
Problem 1 - In a manufacturing process a random sample of 25 bolts has a mean...
Problem 1 - In a manufacturing process a random sample of 25 bolts has a mean bolt length of 10 inches with a variance of .25 inches. Respond to each of the following questions being sure to show all of your work in the space(s) provided. a. Should the researcher use t or z to compute this interval? Why so? b. Compute the 95% confidence interval for the true mean length of the bolts in the overall population. c. Compute...
The diameter of small bolts manufactured at a factory in China is expected to be approximately...
The diameter of small bolts manufactured at a factory in China is expected to be approximately normally distributed with a population mean of 3 inches and a population standard deviation of .3 inches. Calculate a confidence interval which would contain 95% of all possible sample means. Suppose the mean of the sample of 30 bolts is 3.75 inches. Using the interval that you calculated in “A”, what would you conclude regarding this sample of bolts?
The diameter of small bolts manufactured at a factory in China is expected to be approximately...
The diameter of small bolts manufactured at a factory in China is expected to be approximately normally distributed with a population mean of 3 inches and a population standard deviation of .3 inches. Calculate a confidence interval which would contain 95% of all possible sample means. Suppose the mean of the sample of 30 bolts is 3.75 inches. Using the interval that you calculated in “A”, what would you conclude regarding this sample of bolts?
Nuts and bolts are manufactured independently. The inner radius of nuts are normally distributed with mean...
Nuts and bolts are manufactured independently. The inner radius of nuts are normally distributed with mean 1.0 cm and standard deviation 0.015 cm, and the outer radius of bolts are normally distributed with mean 0.95 cm and standard deviation 0.015 cm. Provided that bolt radius is within 0.1 cm of the nut radius, the nut and bolt will fit. What is the probability of a random nut and bolt fitting?
2. You randomly select and measure the lengths of 34 bolts. The sample mean length is...
2. You randomly select and measure the lengths of 34 bolts. The sample mean length is 1.24 inches and the standard deviation is 0.3 inches. Construct a 94% interval of confidence of the mean length of all bolts. Find a point estimate for the mean length of all bolts Verify that the conditions are met to construct an interval of confidence for the mean length of all bolts Calculate the critical Z value to construct a 94% confidence interval (round...
1) A machine is designed to produce bolts with a 3-in diameter. The actual diameter of...
1) A machine is designed to produce bolts with a 3-in diameter. The actual diameter of the bolts has a normal distribution with mean of 3.002 in and standard deviation of 0.002 in. Each bolt is measured and accepted if the length is within 0.005 in of 3 in; otherwise the bolt is scrapped. Find the percentage of bolts that are scrapped. 6.68% 93.32% 3.34% 50% 2) A random variable X is normally distributed with a mean of 100. If...
Thompson and Thompson is a steel bolt manufacturing company. Their current steel bolts has a mean...
Thompson and Thompson is a steel bolt manufacturing company. Their current steel bolts has a mean diameter of 140 mm and a variance of 36. If a random sample of 50 steel bolt is selected what is the probability that the sample mean would be greater than 142.5 mm round your answer to four decimal places
The lengths of steel rods produced by a shearing process are normally distributed. A random sample...
The lengths of steel rods produced by a shearing process are normally distributed. A random sample of 10 rods is selected; the sample mean length is 119.05 inches; and the sample standard deviation is 0.10 inch. The 90% confidence interval for the population mean rod length is __________. Select one: A. 118.99 to 119.11 B. 118.57 to 119.23 C. 119.00 to 119.30 D. 118.89 to 119.51
The diameters of steel shafts produced by a certain manufacturing process should have a mean diameter...
The diameters of steel shafts produced by a certain manufacturing process should have a mean diameter of 5.5 inches. The diameter is known to have a standard deviation of 0.9 inches. A random sample of 30 shafts. (a) Find a 90% confidence interval for the mean diameter to process. (b) Find a 99% confidence interval for the mean diameter to process. (c) How does the increasing and decreasing of the significance level affect the confidence interval? Why? Please explain and...
3. If a population distribution is known to be normal, then it follows that: A. The...
3. If a population distribution is known to be normal, then it follows that: A. The sample mean must equal the population mean B. The sample mean must equal the population mean for large samples C. The sample standard deviation must equal the population standard deviation D. All of the above E. None of the above 4. The internal auditing staff of a local manufacturing company performs a sample audit each quarter to estimate the proportion of accounts that are...
ADVERTISEMENT
Need Online Homework Help?

Get Answers For Free
Most questions answered within 1 hours.

Ask a Question
ADVERTISEMENT